Telephone system and signaling apparatus.



P. R. PARKER. TELEPHONE SYSTEM AND SIGNALING APPARATUS. APPLIUATION FILED NOV. 24, 1906.

1,000,340, Patented Aug. 8,1911. V

F F/21 m 10 K [.9 20 20 1 l7 8 V V I u A, B

1 UNITED STATE i rnnnnnrcx n. PARKER, or omoeeo, rumors.

'PATENT TELEPHONE SYSTEM AND SIGNALING APPARATUS.

$100, 40. Specification of Letters Patent. P t t A 3 1911 Application filed November 24. 1906. Serial No. 344,894. I p v To all whom itmay concern: ate when the shunt of the line is removed, Be it. known that I, FREDERICK It. PARKER, to give anotherpredetermined'signal, pref *a citizen'of the United States of America, erably a supervisory signal. Thusitwwill residing at Chicago, in the county of Cook be seen that the circuit of -the signaling de-v 6 and State of Illinois, have invented a new vice is changed from a series eircuitto a, and useful Telephone System and Signaling bridging circuit, or vice-versmifn-relation-to;

' Apparatus, of which the followingisa specithelin'e, for giving the different signals.

'fica'tion, reference being had to, the accom- Portions of thesystem herein shown-form V pany ing drawings, illustrating thepreferred parts of my co-pending applicationsserial- 10 form of the invention. J Nos. 638,339 and 234,039. Then at. each of" My invention'relates in general to electl'i the substations of such asystem I employ cal systems, for transmitting intelligence and a polarized electrically operabledevice,

for operating electrically-operable devices. preferably a ringer, and a condenser,--and for various purposes, and will-be hereinafter arrange the combination so that the ringer particularly described as applied .to a telemay be operated continuously 'b-y wa direct. phone system, for signaling and talking current applied in ,a certain direction, and

ipnrposes," rendered inoperative and thecir'ouit kept The principal objects of my: invention are open by the condenser when-the polarityaof T to provide improved arrangements of the the impressed voltage is reversed-.- v-.lVl1en:;

line and supervisory signaling devices in an the ringer is, operated, it is operatedby electrical transmitting systennand'improv'ed charging and discharging the condenser.

' pneans for operating same; to provide im Thisarrangement is very advantageous inprovedaneans for using a single signaling certain electrical cirouits,-especial ly in teles device forboth. heline and supervisory sigphone circuits, as it permitsa voltage from, 80

'naljs; to provi e an improved transfer cira source of directcurrentto be noumaliy, cuit for transferring the connections from impressed upon a line, to be used by the subone switchboard to another, and improved scriber for signaling the central station,and means for supervising s'uch connections; to for talking purposes, in a central-battery provide improved apparatusat the substa" system, without allowing current to flow," 85

' tions of the system whereby the subscribers and the current from the said sourcetto op- I may be signaled bya direct current from the crate the ringer to signal the subscriber,

, central station; to provide means whereby when the polarity'of the sourceis reversed a source of direct. current at the central staon the line. Among the advantages of-this 'tion may lie-normally impressed upon the method of signaling is None which is wery Q lines of the system to enable the subscribers i import-ant, namely: eliminating the usual: to signalthecentral station when they sonoise on the lines produced by alternatingdesire. and made. to operate the substation current generators, or ringing apparatus, signaling devices when desired: and to, prowhile ringing the subscribers, Then, too, vide an electrically-operable device which the alternating current ringing equipment 9 40 maybe operated continuously from arsource usually employed is dispensed with. With:

ofdirect current suppliedin a given direcalternating-current ringing-generator sansed tion, and which is incapable of operating on some systems, ringing back through the when the polarity of the saidr source is recentral battery or the relays or other appaverseda v ratus ofthe systelh isa great-disadvantage,

Otherobjects will be apparent from the lVitthv my present, invention .this objectionafollowing specification; able feature is removed. =In0perating my In this present inventionI employ a sigimproved ringer I preferably reverse; the rial-initiating device in connection with each polarity of the central: source of electricity, ot 'the lines of" the electrical system, preferat thevusua l, ringing keys, a 1 ably a telephone system, "and operate same I will novvm'ore particularly describe the,-

in' series with. the line to give a predeterpreferred torn of my invention byreference mined signal, preferably a, line signal, and to the accompanying drawings" in which,- then connect same as a bridge across the Figure l is'adiagram showing two, sub-- "line to be shunted out by the line when the scribe'rs telephone lines extending from ieno circuit of thelatter is closed, and thereby spective substations to ascentral station, and

'- rendered inoperative, and allowed to Opel-.- the 'centrhl -station cirouits'and apparatus,

I of a spring jack C.

Substation A is connected with the central station by' a suitable line circuit comprislngllmbs 1 and 2 which preferably termihate in contact springs 3 and 4, respectively,

normally connected from limb 1 of the line. through operable contacts 5 and 6 of jack C, to'one pole 7 of the source of electricity E, the connection to limb 1being preferably permanently made. The other pole 8 of source E is preferably connected through contact 9 and spring 41 to limb 2 of the line. These connections normally place the signaling device D and source of electricity E in a. series-circuit with the line.

At the substation A the talking appa *atus may be utilized in the usual manner, which is well understood, the signaling apparatus employed hereat being the same as that illus trated in Fig. 3 which will now be described in detail.

In Fig. 3 the ringer F preferably comprises the actuating coils .10 10, permanent m'agnet 1.1, bells 12 12, clapper 13. armature 14, and a spring 15 to normally keep the armature 14 pulled up to one of the poles 16 16' of the cores of coils 10 10.

Contact spring 17 is preferably arranged to operate with armature 1 1 and is preferably insulated therefrom. Contacts 18 and 19 are preferably arranged to alternately engage spring 17, one being out of contact with spring 17 while/the other is in contact therewith. as armature 14 is operated. contacti' 18 being normally in contact with spring 17. Of course I wish it to be under-v stood thatthese contactmembcrs 17. 18 and,

19 may be given various adjustments as desircd, so that they will make or break contact with each other at any desired part of the operation of the ringer armature 14. A condenser 20 is connected from contact 19 to-spring17, and also normally in a series circuit with the coils 10 10 of the-ringer. contact spring] 7, and limbs 1 and 2 of the line. The source of electricity E. preferably a batterv, is normally connected through a key G to limbs 1' and 2 of the line, (in- Fig. 1 whcn'calling plug T is connected w th a line) the positive pole 7 of E being preforably connected to limb Land the negative pole 8 to limb 2; Key (ll-is adapted to reverse the poles ofbattery E on the line whendepressed, springs 21 and 22 then disengaginvention.

A. signaling device I) is.-

ing contacts 23 and 241, respectively, and engaging contacts 25 and 26. respectively. Reversing the battery E on the line, as stated, operates the ringer F will be hereinafter described. l

The apparatus shown in connection with line B is the same as that shown in con ncction with line .1. except for the ringing ap mratus at the substation 13 which is an other form of the ringing apparatus of my Tn Fig. 3, when 'sprin' 17 engages contact 19 it opens the line circuit at contact 18 and shorta-ircnits the condenser 20 on itself only, while with theapparatus shown at substation B, spring 17 engaging contact '19 opens the line. circuit at contact 18' and short-circuits the condenser 20 through the ringer coils 10 10, contact 1-9 being connected between the ringer coils 1O 10 and limb 2 of the line, at 27, to accomplish this result. instead .of to the other side of the. ringer coils 10 10 as shown in Fig. 3. Y

In the plug-cord connecting circuit of Fig. 1 the connecting plugs H and I are normally connected together through repeating coil K, in the usual manner, tip strands 28 and 29 being connected together through windings and of repeating coil K, and sleeve strands 30 and 31 being connected together through windings 34 and of the coil K. The central source of electricity is bridged across the main strands of the plug-cord circuit between windings 32 and and windings 34 and 35. The operatorstransmitter 2-36 and receiver 37 may be bridge-d across the plug-cord circuit. in the usual manner,

by springs 40 and 41 of the listening key on gaging contacts 38 and 39, respectively, when depressed. The ringing key G is constructed and connected to disconnect the main strands 29 and 31 of connecting plug T from the repeating coil K, and to reverse tacts 25 and 26; respectively, which arecoln-- nccted to poles 8 and 7, respectively, of bat tcry E. I

To Fig. 2 I have shown a transfer circuit I adapted to be used with the system of Fig.

1. for transferring the calls and connections from one switchboard to another, or between diii'crcnt sections of the sa meswitchboard. lhe jack C is provided with tip and sleeve contact. springs 48 and 49. respectively, which are connected to limbs50 and 51, re-

p ti ly, of the transfer circuit, whichlimbs terminate in ti"p and sleeve strands 52 and 53, respectively, of transfer plug J. A transfer signaling device M is connected from tip spring 48 of jack 0, through a plug-seat switch H5 at P 18 J, limb-51 l y I W 1,600,340

of the transfer circuit. Jack C, and plug I areat one operators position and plug .T

and ringing key N are at another operators transfer plug J when depressed, the same osition, or at another switchboard. Ring mg key-N is adapted to reverse the poles of battery E on the main-strands 52and=53 o1 as key G reverses the P les of battery E on Strands 29 and 31 of plug I, springs 56 and 57 disengaging contacts58 and 59, respectively, and engaging contacts 60 and 61, re-

' spectively.

The operation of the system is as follows. Ifgsubscriber 'A desires to talk" with subscriber B, helifts hi's' telephone receiver off of -t he-switch-.h'ook,' imtlie usual manner, and

thereby' closes a circuit ofbattery E from pole 7'. through contacts "5 and 6; signaling device D of-'line--A, linib'jl-of't'he linersubstation A, =limb'2 "of the line, jack'spri-ng 4,

and contact 9 to pole 8 of battery "E, which causes'current to flow over this circuitfrom battery E s'uliiciently to actuate thesignaling' device-D a-nd'causesame to give a signal'for co1niect1on. -In answer to the line signal of signaling device D, the operator inserts an swe'ring plug H'into jack C of line A, there-' by'disengaging jack-spring 4 from contact 9, and engagin the'spring-4lw-ith-contact (3" whichnis there y disengaged from contact: 5. Now the circuit of battery E is closer! through winding 32 of repeating coil K, tip strain substation A,li1nb2 of the line, jack spring 4; sleeve strandhBO, and winding 34 of ra seating coil K, the signaling device D being ridged across this circuit from jack spring 3 through the deviceD and contact 6 tojack spring 4,"and shunted by the relatively low resistance of the line so as torender-fit incapable of displaying a signal. The op-' erator now depresses her listening .key which.

connects her telephone'set across the main strands of answeringlplug H in the usual manner, for conversation;with subscriber A; When the :operator learns from subscriber A that he wishes connection with subscriber 13, she inserts the callingplug I into jack' C of line B and thereby closes a -circuit of battery 1* from pole 7, th'roughwinding 33 of repeating coil K, contact 23, spring 21, tipst rand'29', jack spring f-l, signaling (le vice D of line "B, contact 6, jack spring 4, sleeve strand 31, sfnin, "22, contact- 24, and winding 35 of repeating coil K, to pole 8 0f battery E. "The current now flowing through this circuit energizes the-signaling. device D a-nd.causes'same to display a nal, the line circuit beingopen at substation B and therefore not shunting the device D to render 'same inoperative.

is inserted-into'jack Gof -line B, it switches the circuits the same as described shore in ..connection-with plug H and jack C of line A, thus changing the circuit of-signaling 28', jack spring 3, limb Iof'the line,

device D from a series circuit of the line to a bridging circuit of the line. T he operator now depresses her ringingkey G,causing springs '21 and 22 to disengage contacts 23 I and 24, respectively, and to engage contactsj 25 and 26, respectively, to" reverse the poles of'battery' E on 'the line of subscriber B to ring ,the ringer F athis substationns his calling signah v The operation of ringer F will now bcdescribed iii-detail, by reference more portion-- lnrl y to Fig.3, as follows: The normal c115 cult from-:'battery E to ringer F ls'from positive pole 7, through contact 23, spring 21, linib 1, c0ntact l8, spring 17; condenser and 20, ringer coils 10. 1:0, limb 2, spring- 22,

contact 24,, to negative pole 8 of battery E, condenser 20 keeping this circuit opeuaml thereby keeping current from battery E from flowing- "When this circuit conncc tion is first 1 established, condenser 20 is- "charged, the impulse of current chargingv isaine tending to energize the ringer F. To keep the armature 14 of the ringer fronr operat ng, at "ls prefcrable' to employ a spring 15 to keep the 'armatu-re le'pu-lled' to the positionito Whic'lr-the said impulsemof current would operate-same if itaw-er-e not pulled over by spring 1 5, as shown in Fig. 3;. This arrangement keeps thecnru-it of battery E open at the substation and does not allow the ringer to operate. When it is def sirable to 'operate='the ringer F from battery i IE, it is necessary simply to depress tl-lfiT-llllingkey G which reverses the "poles of batter y E on limbs 1 and 2 of the line, asabo've described, and thereby charges the con- 1 denser 20'by an impulse of current in the.

opposite direction, which impulseencrgizes :106 agalnst'the polarizing sp'rlng 15 and opera-to the coils 10 10 of the ringer so that they act the armatme 14 so that the clapper- 1? strikes one of the bells 1.2. This operation I of. the armature 14 disengagcs spring- 17 from contact 18 and engages it with contact,

19. VVhen spring 17 discngages contact 18 it opens the circuit of the line, and when it engages contact 19 it short-circuits the con- 7 denser 20 through sprmg 17 and contuctlfi,

therebydischarging the condenser, immediately after whichsprlng 15 pulls the ar1naturc l tback to its-original position, thus; causing clapper 1-3 to strike the other bell 12;

As spring 17 rciingages contact 18 the condenser 20 is again'charged and:the armature 14 is again operated as at. first. Then the,

' charges the condenser, and the other operathe line circuit were not opened. Withmy enabled to do. away with the ordinary ring- [the subscribers to signal the central. station, und to signal the subscribers from the same ;electricity as it is discharged from the conarrangement whereby the condenser 20 is discharged back through the rin er coils 10 10, t e discharge circuit being mm the condenser 20, through coils 10 '10, connection 27 contact 19, and spring 17, back to condenser 20. With this arrangement it will be seen that the ringer coils 10 1 0 are supplied. with an alternating current, (instead of a pulsating current as in Fig. 3) from a source of direct current, which operates the ringer F practically the same as the ordinary alternating-current ringing generators do'. It will a so be seen that each char e of electricity in :the condenser 20 gives t e ringer two separate and cornplete operations, one operation being pro duced y the charge of electricity 'as it tion being produced by the same charge of denser 20 back through the ringer coils 10 10 in a reversed direction In other words, each impulse of current over the line is utilized twice-in the ringer F. In case the spring 15 is .used on the ringer F of substation B, the discharge from the condenser. 20 will actv with it, or will assist it.

It will be seen that with the above-described ringing apparatus and circuit arrangements, either that shown in Fig. 3 or. at substation B, the main line circuit 1s open while the condenser 20 is-being discharged. This keeps the current consumption to a; minimum and eliminates the waste of current which would necessarily be present if arrangement the only current necessary is that tocharge the condenser, which is a very small amount in ordinary telephone ringing systems.

By the use of the apparatus and circuit arrangements of my present invention I am ing apparatus. at the central station of a. telephone system and ring the subscribers alternatingmwrent ringers or pulsating current ringers from the common source of direct current at the central station. It will also be seen that by the use of my in;- vcntionI ani enabled 'to keep the telephone lines of a'systcm normally charged with a central source of direct current to enable source when desired, without normally los mg any current from the source. I may also use thissarne source ionsupplying the substation transmitters. with current for talking-purposes. 1',

- VYith this improved ringing apparatus of my present invention, it will be seen that the noise onthe lines of a'telephone system,- due to the induction of the ordinary alternatingrcurrcnt or pulsating currentringing apparatus, is done away with. In rlngmg subscriber B, as just described above, the operator also restores her listening key to its normal position. After ringlng sub-- scriber B. the ringing key G is also restored to its normal osition. When subscriber B responds to hlS call and takes his-receiver. from the switch hook, he closes the circuit of battery E over his 1111c and thereby causes the latter to shunt the signaling-device D which is now bridged across his line as de scribed, and extinguish its signal. Now the ceiver upon its switch hook, he breaks the circuit .of his line at his substation and thereby takes the line shunt away from his.

signaling device. D and allows thelatter to operate by means of currentfrom battery E over the circuit 32, 2s, 3,;D, 6, 4, 30 and 34;,

to display a signal for disconnection. When subscriber B hangs hisreceiver upon its switch book he causes his signaling device D to display a signal for disconnection, inv a manner similar to that just described for subscriber A. If eithersubscriber'A or 'B now desires to signal the operator for any purpose, be may operate his signal D intermittently by raising and lowering his'switch hook in the usual manner. When the operator receives both disconnect signals, she withdraws the plugs H and I rom their respective spring jacks and thereby" extinguishes the supervisory or disconnect signals D D and restores all circuits and apparatus to their normal condition.-

If subscriber A has called for subscriber. B and the latter is on another switchboard,-

or his jack is outof reach of the A'-line op 'erator, then it is. necessary to use the 'trans.- fer circuit of Fig. 2 for making the connection. In this case the A-line operator in sorts the calling plu I into the transfer jack C, which extends the cord circuit to transfer plug J at the-B-line position. Then the A-line operator instructs the B-line op; erator (in any suitable manner') to insert the transfer plug J into jack 0 of line B.

When plug I is inserted. into jack 0,, a circuit is closed. from pole 7- of battery E through winding 33, contact 23, spring 21, I

tip strnnd'29, j ack spiing -18, signaling device M at the A-line position, plug-seat switch contacts- 55 54 at the B-line position, conductor 51, ja'ck spring 49, sleeve strand 31, spring 22, contact 24,. and Winding 35, to pole 8 of battery E, which causes signaling device M to operate by current from battery E and thereby display a signal.

.When the'B-line operator inserts plu'g'tl i into .jack C of line 13, she opens switch conthrong Signaling device -M- and extinguiahtacts 54 55, thereby opening the circuit ing its signal to indicate to the A-line openator thatv the plug J has been removed from its seat for connection with line B, and also switches the circuits of line B as described inconnection with line A when plug H is inserted'into jack C thereof. "The signaling device D of line B now 0 erates and displays a signal, the circuit o line B bea'n'ce shunt around his signaling device D and thereby deenergi'zcs D and extinguishes its signal which indicates to the B-line operator that subscriber has answered his citllgfllhe 'titllilllgcltdlllt betweensubthe cord circuit of Fig. '1, the l'nain strands.

n hug device 1) which now operates, due

'o removal the line shunt, by current ifromjjbatterydl over thecircuit from pole .7, through \vi'nding33, contact 23, spring 21, tip strand I2$), 'j ack spring 48, conductor 50, contact 58, Spring 5G,tip strand {32, jack spring 3' of line signaling'devicc 1), contact 6, jack spring 4, sleeve strand 53, spring 5 ,rqn'ta'ct 5,), conductor 51, jack spring 49, strand 1, spring 22, contact 24, and "Winding 7 to pole 8,'and thereby conveys 'to the B-lmo operator the signal "for tllSOOllnection. The B-line, operator now with-' draws plug J from jack (lot line and therebybrcaks the circuit. of battery I) from signaling device I) and extinguishes its sigto theirnorh' alcondiiion.

when the plug J 1s replaced to its plug s at,'fi t cl the contacts 5 1 5'5 a'nd"t||ei.'el y the'cii'chitof battcryll through sigcloses i pallnfdev ce M, over the circuit l'ic'rclnbcfore dcscril'icd, which thereupon displays a signal to indicate to. the A-line "operator Qthaflthe plug'J has been removed l'rom its ja ckQ TVVhen' th'e A-li'ne operator receives nal. she withdraws the plug 1' from cf 0 and thereby disconnects battery 'ng 'devii" A ber A. gi vrs h disic usual fl nanner, \vhcreopera tor Withdraws the aclg (l and thereby rc- "ts tind apparatus to their norapt-m th pa .11. ne star all'circi. n

the 's'ame'tiine restr'n' 'ing the circuits 'l' and extinguishers If desired, the transfer circuit may ebe provided with a listening key similar to that of Fig. 1, toenable'the B-line operator to cut in on the line and talk to the subscribers.

For the ringer F I- may use any suitable polarized ringer. If desired I ma usean ordinary alternating' current ringer a'nd place'it in such a position that grav ty will iold the armature 14 to one of the poles 16 16. In this case the adjustment of the po-' larization will depend upon the position of the rin er:

For t e signaling devices D, D and M, I may use an electric signal lamp in series with an impedance,a relaycontrolling a signal, or any suit-able electrically operable device. For the battery E I may use a. suitable direct-current gener'atorif desired" In this invention I do not wish to be limited to the exact details, nor jo'the particular apparatus, herein shown, as many modifications may be made therein withoutdeparting from the scope of" the appcndcd"" claims:

:What I claim:asimyinvention is: I

1. A telephone line extending to a substation, a polarized alternating-currcnt ringer atthe substation, a source of dire'gt' current impressed upon the line, a condenser 'at the substation to normally keep current of the said source 'm'ifn'essed tllll't-Oll,

whereby the said primary and secondary circuits are opened and closed Internet-, tently, to produce pulsations of current. of

' opposite polarity throughthejsaiid deviCe' A, primary circuit comprising a polari'ze'd electricallymperabledevice, a condenser and a source of electricity, a secondary CII m cuit comprising the said do and madenser, and switching mechanism o mrated by the said deviee vvhen' the proper polarity 0 oi the said source is ii'nprcsstal' thereon, \vllci'ebyJl e said primary and smzondarylcircuits are opened and closed iniermittently during the operation of thesaid device, the condenser being thereby alternately charged and diseharged throughtlie siiid device; I p i 4. An elcctricalsignaling lineg a source of signaling current, switching inechanism I for applying current of polarity to the line, and a substation on the line equipped with a polarized signaling device, a condenser, and switching mechanism adapted to be actuated by the said device to open the circuitof the line and close the condenser circuit through the said device,-

iutern'iittently, substantially as set forth.

5. A telephone line circuit, a signaling battery at the central station, switching mechanism for applying battery current of requisite polarity-to the line, a substation .on the line equipped with a polarized signal bell and a condenser in circuit therewith, a local circuit for the condenser, and switch contacts controlling the circuitof the line and the local circuit of the condenser, alternately engaged to effect the actuation of said bell.

6. In a'telephone system, the combination With atelephone line extending from a substation to a central station, of a polarized ringer and associated condenser at the substation, mechanism controlled by the ringer for opening the said line circuit and simultaneously efiiectingthe discharge of the condenser, and means at the central station for applying current of requisite polarity to the line to effect the operation of the apparatus' atthe substation.

7; The combination with a telephone line, of a source of direct current, switching mechanism adapted to apply the current to the line, a substation on' the line equipped with a polarized ringer and condenser normalty connected to the line, and circuit-controllingmechanism adapted to be actuated by the ringer to sever the line and short-circuit the condenser through the ringer, int-erniittent'ly,"substa.intially as set forth.

8. A signaling. circuit comprisiniz' a line,-

polarized signaling apparatus, and a. con-- denser; and means for opening the said circuit and simultaneously; causing the discharge of the condel' ser through the signaling apparatus, intermittently, under favorable electrical conditions.

- 9. An electrical circuit comprising; polar ized' apparatus and a condenser, andv mechanism controlled. by the said apparatus for opening the said circuitand sinmltaneously causing the. discharge of the condenser, intermittently, under favorable electrical conditions. p t 10. An electrical'circuit comprising a polarized electrical]yoperable device and a condenser, and 'ine'chanism controlled! by the said device rm ipen ing the'sa'id circuit and simultaneously causing the di .harge of the condenserthrough the sa-id dc'v .e, int-'ern'littently, when a potential of proper polarity is impressedupon the circuit.

11. A series circuit comprisinga line, a

polarized -electrically-operable demise, m and a condenser; a local-circug for thesaid de- Vice and condenser, and sw tch contacts COI1- andwhereby the said series circuit is kept trolled by the said device andadapted to control. the circuit of the line and the local circuit of the said device and condenser, respectively, under favorable electricalconditions. I

12. polarized electrically-operable device and a condenser connected in circuit therewith, a local circuit for the condenser, and a plurality of switches controlled alter: nately. by the said device when apotential of requisite polarity is impressed thereon, to control the main circuit and the local, cirgcuit of the condenser, respectively;

13. A. line, a polarized electrically-0pm able device and a condenser associated there with, automatically-actuated means controlled hy the said device for opening the line and simultaneously effecting the discharge of the condenser, and means for applying current of. requisite polarity to the line to effect the operation of the said de vice.

'14. A series circuitcomprisin" a source of direct current, an electrically-operable device, and a condenser; the condenser normally keeping the said circuit conductiv elyincomplete, and mechanism controlled by the said device whereby the latter may be operated continuously from the said source,

circuits are opened and closed intermittently fduring the operation of the said devicepthe condenser being therebyalternately charged and discharge 17. A primary circuit including a polarized electrically-operable device, a condenser and a source of electricity, a secondary circuit including the condenser, and mechanism under control of the said device whereby the,

said circuits are opened and closed intermittently when the proper polarity of the stud source is impressed upon the primary circuit, the condenser being thereby alternatelycharged and discharged.

18. .A primary circuit including'an elec triwilly-operable device, acondenser and a. source of electricity, a secondary circuit cluding the said device and condenser and, in. under control of the said devic, the said circuits are-openedfland of supply is intermittently broken while the discharge circuit of the condenser is closed.

20. A telephone line extending to a sub station, a polarized ringer at the substation, a source of direct current impressed upon the line, a condenser at the substation to normally keep current from flowing over the line. and'switching mechanism whereby the ondcuserlis. alternately charged and discharged when the proper polarity of the said source is impressed upon the line, whereby the ringer is rung continuously. the said mechanism opening the circuitof the' line as the condenser is being discharged.

An electrical signalingliue, a source of signaling current. means for applying the current to the line. and a substation on the line equipped with 'a signal-initiating device, a condenser, and switching mechanism for opening the circuit of the line and simul- 'taneously causing the discharge of the condenser, intermittently, substantially as set 'forth.

22- A signalin, circuit comprising a line, polarized signaling apparatus, and a condenser; and means for opening-the said circuit and simultaueously causing thedischarge of the condenser, intermittently, under favorable clectriwd conditions.

- '23. A signaling circuit comprising a source of electricity, a signal-initiating dc rice and a comlcnscr, and mcchanism'for openingthe said circuit and causing the discharge of the comlcuser. intermittently, din:- ing the operation of the. said device.

24:. A signaling circuit comprising a source'- of electricity, :1 signal-initiating device. and a condenser. and'mcchanism for opening the said circuit and causing the discharge of the condenser through the said device, interu'iittently,during the operation ot'the latter.

.35. The combination with an electrical circuit com 'ntising a source. of electricity. an electrically-operahle device and a co'mlcnser.

. of mechanism for opening the said circuit and causing the discharge of the condenser,

intermittently, during the operation of the said device.

26. The combination with an electrical circuit comprising a source of electricity, an

electricallycpera e device and a condenser, of mechanism for opening the said circuit and causing the dischar e of the condenser through the said device, intermittently, during the operation of the latter. a y

27. A line circuit comprising a source of electricity, an electrically-operable device and a condenser; a local circuit for the condenser, and switching mechanism under control of the said device and arranged to control the said line circuit and the local circuit of the condenser.

28. A main circuit comprising a source of electr1c1ty,'an electrically-operable device and a condenser, a local circuit forthe condenser. and a plurahty' of switches controlled alternately by the said device for I controlling the said main circuit and the local circuit of the condenser.

'29. The combination with a source of direct current and an electrically-operable derice to be operated thereby, of means for keeping the circuit of the said source eon tinuously condactively-incomplete during 'the operation of the said device.

30. An electrical circuit comprising a,

source of direct current, an electricallyoperable device and a condenser; and mec anism whereby the said device may be operated continuously from the said source, the condenser and the said mechanism cooperating to keep the circuit of the said source continuously conductively-incomplete during the op'eration of the said device.

31. In a signaling circuithavin a signaling device and a condenser un er control thereof to be charged and discharged inter mittently, and also a source of electrical supply, means under control of the said device whereby the circuit of the said source of supply is intermittently broken while the discharge circuit of the condenser is closed.

As inventor of the foregoing I hereunto subscribe my name in the presence of two subscribing witnesses, this 19th day of Novcmber,-1906.

FREDERICK R.

Witnesses: p

tour. (.lr. PARKER, PATRICK J. Pownns;

PARKER.- 

